Clutch plates are generally manufactured with an annular metal backing plate to which is secured an annular friction member. As taught U.S. Pat. No. 4,260,047 to Nels, issued Apr. 7, 1981, and assigned to the assignee of the present invention, it is known to stamp successive quadrants which are secured together with a tab and slot arrangement to form the annular friction member.
With conventional transmission clutches, which are of relatively small diameter, the annular friction members can be transported from one machine to another or stored in inventory without the tab and slot arrangement disengaging. However, when this process is attempted with larger annular rings, such as those required for torque converter clutches, the resulting annulus is too frangible, such that storage and transportation of the friction material alone is not viable.
To overcome this drawback, it has been proposed to blank each segment directly onto the clutch pressure plate. However, significant difficulties were found in attempting to align the adjacent friction segments. Thus, a great deal of scrap or rework is required with this method.
It has also been considered that a complete ring could be stamped from a sheet of material. However, this process results in a great deal of waste and the friction material is expensive.